| 摘要 |
PROBLEM TO BE SOLVED: To accurately control the inner pressure of an air bag by changing the amount of gas exhausted out of a vent hole during deployment of the air bag. SOLUTION: A control valve 30 formed by adhering a plate piezoelectric element 31 to a metal protector 32, a vent hole 29 opened/closed by the control valve 30 and an inner pressure detecting means 35d for detecting the inner pressure of an air bag 21 are provided on a retainer 19 for supporting an inflator 20 and an air bag 21 for an air bag device. The piezoelectric element 31 closing the vent hole 29 during no power supply is curved with power supply to open the vent hole 29 for exhausting gas in the air bag 21 to the outside. The opening of the vent hole 29 is feedback controlled in accordance with the inner pressure of the air bag detected by the inner pressure detecting means 35d so that the change in inner pressure of the air bag with the passage of a time can correspond to an preset inner pressure pattern. |
